[SOLVED] Magene Gemini 210 (S3+) BLE\Bluetooth not pairing

Problem: Magene Gemini 210 (Also known as S3+) sensor in Speed mode is not discovered as Bluetooth (BLE) device by Zwift for android (and possibly other), but discovered as Power Source (but doesn’t work as power source).

Solution: Upgrade Magene Gemini 210’s firmware to version 0.104


  1. Download Magene Utility
    Direct links: Android | iOS
    QR Codes:
    Android app is not signed with Google cert, so, you should allow untrusted sources.

  2. Take off your Magene Gemini 210 device and put on a table next to your phone.

  3. Ensure you have fresh battery in Magene sensor and phone charged at least for 20%

  4. Open Magene Utility app. Swipe down. You possibly will see no devices in the list. Get your Magene Gemini 210 sensor, remove battery, wait few seconds and put battery back. Put device battery facing table (and you see LED indicator). Swipe screen down again to refresh (possibly, few times). Now you see your device in list. Next steps must be completed in a row, to avoid sensor fall asleep.

  5. On your phone, tap on your device in device list. You will see firmware update button. Press upgrade button, and then upgrade button again.

  6. Firmware upgrade starts. Do not exit app. Tap periodically white space on a screen to avoid phone go asleep during firmware upgrade process.

  7. Firmware upgraded

  8. Take away a battery from Magene Gemini 210 to power it off for about 30 seconds. Insert battery back and set mode to speed (green led blinking after battery set)

  9. You are awesome!

In pictures (Taken from Android):